'Dumb' in the Bible

Then Daniel, whose name was Belteshazzar, was stricken dumb for a while, and his thoughts troubled him. The king answered and said, Belteshazzar, let not the dream, or the interpretation, trouble thee. Belteshazzar answered and said, My lord, the dream be to them that hate thee, and the interpretation thereof to thine adversaries.

and when he had spoken unto me according to these words, I set my face toward the ground, and was dumb.